The present invention relates to a navigation system, which searches for a corresponding location from an input location by the use of a search list and searches for a target location from a selected facility type by the use of a search list.
In a navigation system disclosed in JP-A-10-111141, location names of various facilities are preliminarily stored as a search list and a target location is searched from an input location name by the use of the search list. This search is conducted alphabetically in Japanese 50-alphabet system. The searched location is used as a destination or a passing point in a travel route guidance. It is also used to indicate a road or area map, which includes the searched location.
In another navigation system, a user registers his/her home location and friend""s locations. The registered locations are used in a travel route guidance or in map display.
However, the above Japanese alphabetical search (alphabet-based search) method uses the search list, which stores the location names of facilities and the like. The registered locations input by the user cannot be subjected to the alphabet-based search. As a result, the user-registered locations must be searched in another method other than the alphabet-based search method.
Still another navigation system has a function of a facility search or a surroundings search in addition to the alphabet-based search. The facility search or the surroundings search is conducted by the use of a search list, which stores data of names of locations, coordinates of locations, types of facilities and the like. This navigation system will be useful if registered locations input by a user can be made a subject of:the facility search or the surroundings search.
It is therefore an object of the present invention to provide a navigation system, in which registered locations input by users can be made a subject of an alphabet-based search.
It is another object of the present invention to provide a navigation system, in which registered locations input by users can be made a subject of a facility search or a surroundings search based on a facility type-based search.
According to the present invention, a navigation system has a rewritable memory which originally stores data of a plurality of locations. When a user inputs a new location other than the plurality of locations, the navigation system registers and stores data of the new location in the rewritable memory in addition to the data of the plurality of locations. When a user requests a search of a target location from the external side, the navigation system searches the rewritable memory for the target location with reference to the data of the plurality of locations and the new location. The navigation system displays on its display unit the target location.
Preferably, the target location is defined by a location name, and the navigation system conducts a search based on alphabets. The target location may be defined by a facility type, and the navigation system conducts a search based on the facility type. In addition, the target location may be defined along with a request for a surrounding search, and the navigation system conducts searching for surrounding locations other than the target location.